Does Mom’s Diet Affect Baby’s Sex?

The research shows a higher calorie intake around the time of conception can shift the odds of having a son from ten to 11 boys in every 20 births. The effect was such that the more women ate, the more likely she was to have a boy.

As well as consuming more calories, women who had sons were more likely to have eaten a higher quantity and wider range of nutrients, including potassium, calcium and vitamins C, E and B12.

Apparently, the women in the study who consumed fewer calories were more likely to give birth to girls. Even though it’s the sperm, not the egg, that decides the sex of the offspring, it is believed that “lean times are linked with daughters” throughout the animal kingdom—this phenomenon has been studied in insects, horses, cows, and deer. Dr. Fiona Mathews, the woman behind this study, shares the possible reasons for this occurrence:

‘Boys breast feed for longer and for more,’ she says. ‘There is evidence from traditional societies that mothers invest more time in bringing up boys. And if a mother has plentiful resources then it can make sense to invest in producing a son because he is likely to produce more grandchildren than would a daughter. However, in leaner times having a daughter is a safer bet.’

The theory does seem a bit flimsy—especially since the calorie consumption of the fathers wasn’t taken into account here—and one commenter makes a very good point:

No this can’t be right doesn’t Posh Spice have three boys? Nobody could convince me that she had higher food intake than a gnat.